While the group was hardly a liability last season, there were tons of inconsistency while allowing 43 goals in 38 matches. This tied for fifth in the league, but they would need to do better to secure a top spot in the table.

The squad took a big first step toward achieving this goal when it replaced Pepe Reina with Simon Mingolet in goal. The young keeper has been incredible already this season as he stakes a claim as one of the best players in the league at his position.

Liverpool also added Kolo Toure, whose experience with Manchester City will be invaluable with the young team this season.

As a result, the Reds already have three clean sheets in three matches, including its most recent 1-0 win over Manchester United to stand alone on top of the table.

Mamadou Sakho will be able to fill in right away at centre-back, although he is versatile enough to play left-back as well if needed. Still, he has loads of experience of competing against top competition with both Paris Saint-Germain and the French national team.

His ability to stop attacks at a high rate while avoiding mistakes will help provide a steadiness in the middle of the defense. He and Daniel Agger can combine to make things tough on opposing offenses.

Meanwhile, Tiago Ilori provides even more cover and, at 20 years old, could end up being a quality contributor down the line. He also allows Sakho to move to the outside if Jose Enrique or Glen Johnson need a rest.

Adding these two young players to a unit already playing well is a huge move that will affect the entire Premier League. At this point, it would not be surprising if Liverpool held opponents to 30-35 goals over the course of the season.

On the other hand, every other top team has question marks in that area. Manchester City will struggle without Vincent Kompany for the near future, while Manchester United and Arsenal still have questions at centre-back.

As for Chelsea, they will only be as successful as David Luiz allows them to be, which could end up being a bad thing.

However, Liverpool have gotten stronger and have passed their rivals to create the best defense in the league.

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